Cloud computing delivers computing resources over the internet. It allows users and businesses to use software and hardware managed by third parties. There are three main service models: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). The document discusses how cloud computing can help address problems with desktop-based CAD by providing virtually unlimited computing resources, allowing for collaboration and data sharing in the cloud, and making CAD accessible from any device.